LONDON (Reuters)    Ecotourism is causing a lot of damage to wildlife and may be endangering the survival of the very animals people are flocking to see, according to researchers.
Biologists and conservationists are worried because polar bears, dolphins, penguins and other creatures are getting stressed and losing weight and some are dying.
"Evidence is growing that many animals do not react well to tourists in their backyard，” New Scientist magazine said.
The immediate effects "researchers have noticed are changes in behavior, heart rates. or stress hormone levels but they fear it could get much worse and over the long term “ could endanger the survival of the very wildlife they want to see. ”
Although money produced through ecotourism, which has been growing at about 10-30 percent a year, has major benefits for poor countries and people living in rural areas, the Swiss-based World Conservation Union (IUCN) and some governments fear not all projects are audited（审计） and based on environmentally friendly policies，according to the magazine.
Transmission of disease to wildlife，or small changes to wildlife health through disturbance of daily life or increased stress levels, while not obvious to the casual observer, may translate to lower survival and breeding，” said Philip Seddon , of the University of Otago in Dunedin, New Zealand.
Scientists have noticed that bottleneck dolphins along the northeastern coast of New Zealand become nervously excited when tourist boats arrive. Similar changes in behavior have been observed in polar bears and yellow-eyed penguins in areas visited by colorists are producing smaller babies.
Conservationists are now calling for more research into the effect of ecotourism on animals and say the industry must be developed carefully. They also want studies done before new ecotourism projects are started.
“The animals’ welfare should be very important because without them there will be no ecotourism，” said Rochelle Constantine of the University of Auckland in New Zealand
Which is not discovered to have changed in animals disturbed by tourists?

A．behavior

B．birth rate

C．hormone levels

D．heart rates

We may learn from the text that _____.

A．ecotourism must be developed properly

B．polar bears are losing weight without enough food

C．all the poor countries have stopped ecotourism

D．money produced through ecotourism should be spent on wildlife

Which of the following is NOT mentioned in the text?

A．Many animals do not react well in their backyard

B．Studies should be done before new ecotourism projects are started

C．Ecotourism has been growing at about 10—30 percent a year.

D．polar bears in areas visited by ecotourists are producing smaller babies.

What Rochelle Constantine said in the last paragraph implies that _____.

A．if people want to get high income, they must develop ecotourism

B．animals have rights to live their own life

C．animals are people's good friends

D．people should take good care of wildlife